ABSTRACT Background: Color changes that are detectable to human eye can affect the esthetic appearance of ceramic veneers. The purpose of this study was to evaluate and compare the effect of artificial accelerated aging on the color of ceramic veneers cemented with different resin cements. Materials and Methods: Sixty discs were prepared with 0.5 mm thickness, 30 discs made from IPS e.max press (Ivoclar Vivadent) and 30 discs were made from VITA Enamic (VITA Zahnfabrik). The discs were cemented with three resin cements: Variolink Veneer MV 0 shade (Ivoclar Vivadent), Rely X veneer Translucent shade (3M ESPE) and NX3 Nexus Clear shade (Kerr Corporation) with 0.1 mm thickness. The spectrophotometer Easyshade Advance was used to measure the color parameters (Lightness, axis a* of chroma and axis b*of chroma) immediately after cementation, after 150 and 300 hours of aging. The specimens were subjected to artificial accelerated aging in Accelerated Weathering Tester. Color change greater than 3.3 was considered unacceptable. One-way ANOVA, paired t-tests and Bonferroni adjusted t-test were used for statistical analysis (p <0.05). Results: Artificial aging caused high significant color change in both ceramic types, but there were non-significant difference in color change among the three resin cements used. The color change was between1.997-14.8 after 150 hours and it was between 2.179-15.68 after 300 hours. The color change of e.max discs after aging were within acceptable limit<3.3 whereas Vita Enamic specimens had shown unacceptable color change >3.3 after aging. Conclusions: The majority of color change after aging related to veneering materials while resin cement have only slight effect on color change after aging. IPS e.max had shown an acceptable color change after aging, so it is suitable for fabrication of restorations in esthetic zone while Vita Enamic should not be used in esthetic zone since it has poor color stability according to the results of this study.
This research Sought to Determine the Relationship and impact between the tax knowledge in dimensions of the tax compliance costs (monetary costs, time costs, psychic costs) Since the sample included 81 individuals represented by the Executive directors and Financial and Accountant working in the Joint-stock company, A questionnaire was used as a tool for data collection and its analysis. For the purpose of analyzing the research data the statistical package for social science, SPSS. The most important tools used in the statistical analysis are:(standard deviation, and simple linear regression, percentages, arithmetic mean, Cronbach's alpha, F-test, T- Test). The research found a weakness attenti
... Show MoreCompensation is one of the most discussed topics in the arena of civil law that requires research About solutions to the damages that arise from the promotion of extremist ideas, which were imposed by the developments taking place in society and the increasing escalation of accidents and their increasing risks, which now threaten individuals and their property on a daily basis in large numbers, as the injured party always seeks to require quick compensation from the person responsible for the damage that satisfies his desires and removes the effects of the damage caused, The importance of compensation increases if the violation affects a person’s physical integrity or his right to life, which is the highest right recognized for humans in
... Show MoreThe research presented the tagged (aesthetic and expressive characteristics in the works of Jean Dubuffet), so the research objective was: to know the aesthetic and expressive characteristics in the works of (Jean Dubuffet), and the research included four chapters. The aim of the research, the limits of the research, and the definition of terms. The second chapter included four topics. The first topic presented the aesthetic essence and style, while the second topic dealt with expressionism: approaches in concept and meaning.
While the third topic was preoccupied with presenting the aesthetic and expressiveness in the drawings of modernity and beyond, while the fourth topic dealt with: Jean Dubuffet and the experience of raw art. Th
This research aims to clarify the principles governing the exploration and utilization of outer space, emphasizing the role of international law, particularly international criminal law, in addressing crimes committed beyond Earth whether aboard spacecraft, the International Space Station, or in outer space generally. It examines relevant international treaties governing outer space activities, evaluates their strengths and ambiguities, and highlights deficiencies in their provisions. Furthermore, the study analyzes traditional principles of state criminal jurisdiction territoriality, nationality, universality, and protection and assesses their applicability to offenses committed in outer space.
A.R. Ammons's Garbage is a unique poem in all measures, starting from the title to the subject matter of the poem. Though it discusses the ecological repercussion of waste management, the long poem is written to shed light on the correlation between language\poetry and garbage. The paper argues that in his examination of language\poetry and garbage as both reflectors of human life and experience, Ammons claims that redemption is possible through both language and garbage by scrutinizing human experience whether low or high, mundane or sacred. This paper tries to examine Ammons's efforts to use the farfetched metaphor of garbage to discuss language and poetry-writing.
Abstract
The research addresses the specification table and the extent of its use in developing achievement tests, as well as detects the obstacles to its use through a sample of (120) respondents from the faculty members in some Baghdad schools and colleges. After unpacking and processing the data statistically, the research reached several results: the study sample do not use the test map in the development of their tests, as their percentage reached (82%) and there are no statistically significant differences in the use of the specification table by the sample members according to their place of work or the number of years of experience. The results also revealed the most important reasons that prevent the use
... Show MoreThe internal administrative spaces of the interior designer formed an obsession for their development and for finding solutions and treatments to advance to enhance the state of adaptation for their employees by providing a healthy, appropriate and sound environment for work and production. . The first chapter focuses on laying theoretical foundations to show what health materials are used in the administrative spaces of the training directorates of the Ministry of Education in Baghdad. The second chapter dealt with the knowledge of health materials, their impact and effectiveness in the interior space, and the variables of their functional characteristics and their work in the interior spaces in a way that enhances the development of
... Show MoreWhich was entitled : Aesthetic and dramatic dimensions of silence in the feature film , and the researcher clearly define after removing the confusion existing in some authorized sources , as for the concept of silence , adopted in this research is : the death of the audio stream , Hence the researcher shed a light on the aesthetic and the dramatic role of silence in the feature film , through the handing of the silent scenes ( absolute silence ) in the film research divided this research into four chapters . This first Chapter includes : methodological framework , which represents the research problem , which came with the following question : what is the mechanism of productive silence to the
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Westernization is a term not familiar to our scholars at the beginning of the emergence of translation from Western literature, sciences and arts in its detailed form now.
Westernization was not an issue that those Greeks, Persians, Romans, Indians and others worked on translating those sciences and cultures. Rather, it was a process of transferring a new philosophy and logic that had not been previously seen by the Arabs, so they were affected by it in a strange way, to the point of fascination by some of them. For this reason, this research came to clarify these issues and address them within the scientific methodology.
Motives: The research deals with the issue of urban sprawl on agricultural lands. It is an urban problem caused by rapid urbanization and poor planning. It is considered one problem that threatens cities with environmental and health disasters. It also threatens agricultural life and the green belt surrounding cities. Changes in urban sprawl on agricultural land are associated with complex processes that lead to multiple social, economic, political, and environmental risks and thus pose a threat and an obstacle to the sustainability of cities. Aim: The research aims to study and evaluate the reality of the city of Baghdad and the extent of its ability and flexibility to withstand the disaster of urban sprawl on agricultural lands. T
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